Solid electrolytic capacitors (e.g., tantalum capacitors) have been a major contributor to the miniaturization of electronic circuits and are often used in devices such as implantable defibrillators and pacemakers, where the smaller circuitry results in a device that is not only easier to implant into the patient, but that also allows for the inclusion of a larger battery in the device. The use of a larger battery, in turn, prolongs the longevity of the device. One manner in which the area occupied by solid electrolytic capacitors has been reduced is to incorporate a plurality of solid electrolytic capacitors into a single module as described in U.S. Pat. Nos. 6,185,088, 6,243,605, 6,251,124, and 6,477,412 to Youker, et al., where the arrangement of the capacitors in the module results in the module occupying less space on a circuit board than if the bases (e.g., anode termination ends) of each of the capacitors in the module were individually mounted onto the circuit board. However, one problem with the module design described in U.S. Pat. Nos. 6,185,088, 6,243,605, 6,251,124, and 6,477,412 to Youker, et al. is that the anode termination ends of the capacitors can become misaligned or non-planar during the assembly of the module into its outer shell, as well as when the cathode terminations are connected to a conductor. As a result, one or more of the anode termination ends may not be planar with the remaining anode termination ends so that sufficient contact between each individual anode termination and the circuit board is not made after the module is mounted to the circuit board. In addition, a conductor that connects the cathode termination ends of the plurality of solid electrolytic capacitors to each other and runs down a side of the module to the circuit board may vary in height compared to the height of the plurality of solid electrolytic capacitors, which can also affect the integrity of the connection between the conductor and the circuit board or the connection between one or more of the anode terminations and the circuit board due to the lack of planarity of the lower surfaces of the capacitors, the upper surfaces of the capacitors, or both.
As such, a need remains for a solid electrolytic capacitor module that includes a plurality of solid electrolytic capacitors, where the anode terminations and any conductor or lead frame used to connect the cathode terminations to the circuit board are planar with each other so that the module can be mounted to the circuit in a mechanically and electrically stable manner.